Downhole scraping and/or brushing tool and related methods

Abstract

An improved and enhanced spring loaded downhole tool for cleaning well casing bores comprising a mandrel, at least a first insert having a passageway therethrough, and at least a second insert, wherein both the first insert and the second insert are selected from at least one of a spring loaded scraper insert and at least one wire brush insert, and further wherein the first insert and the second insert are slidingly received within a slot on a first mounting portion on the mandrel and a slot on a second mounting portion on the mandrel, from the outermost respective ends, and wherein the first insert is secured by a first retaining sleeve and the second insert is secured by a second retaining sleeve. Also disclosed is a unique method for cleaning a section of casing with a downhole tool, as herein disclosed.

1. A downhole tool for connection in a tubing string for use in cleaning wellbores, comprising:
 a mandrel assembly comprising an elongated tubular mandrel with a passageway extending axially through the mandrel and a retainer mounted on the mandrel such that relative axial and rotational movement with respect to the mandrel is limited, the retainer having a cylindrical outer surface, at least one axially extending groove and one annular groove formed in the outer surface; and a wellbore cleaning element mounted to extend from the exterior of the mandrel into contact with the wellbore when the tubing string and tool are moved within the wellbore; and 
 a sleeve mounted on the exterior of the mandrel for contacting the wellbore, axially extending ribs on the interior of the sleeve of a size and shape to mate with the ribs on the exterior of the retainer to restrict relative rotation of the sleeve with respect to the mandrel, and an annular groove on the interior of the sleeve located adjacent to the axially extending groove in the retainer, spheres located in the groove on the retainer, the spheres extending into the groove in the sleeve whereby relative axial movement between the sleeve and the mandrel is limited. 
 
     
     
       2. The downhole tool of  claim 1  additionally comprising a geometric shape on the exterior of the mandrel and a complementary geometric shape on the retainer engaging the geometric shape on the mandrel to limit rotation of the retainer with respect to the mandrel. 
     
     
       3. The downhole tool of  claim 2  wherein the geometric shape on the mandrel is polygonal. 
     
     
       4. The downhole tool of  claim 2  wherein the geometric shape on the mandrel is hexagonal. 
     
     
       5. The downhole tool of  claim 1  wherein the retainer is a sleeve. 
     
     
       6. The downhole tool of  claim 1  wherein the retainer has a one-piece construction. 
     
     
       7. The downhole tool of  claim 1  wherein the cleaning element is mounted in a slot in the exterior of the mandrel. 
     
     
       8. The downhole tool of  claim 1  wherein the cleaning element is resiliently urged in a direction radially away from the mandrel. 
     
     
       9. The downhole tool of  claim 8  wherein the cleaning element is selected from the group consisting of a brush and a scraper. 
     
     
       10. A downhole tool for connection in a tubing string for use in cleaning wellbores, comprising:
 an elongated tubular mandrel, a slot in the exterior of the mandrel and a brush assembly mounted in the slot, 
 the brush assembly comprises: 
 a biasing member having a plurality of passageways, the passageways extend radially through the biasing member when the biasing member is mounted on the mandrel; 
 an independently movable brush element mounted in each of the plurality of biasing member passageways, each brush element comprising a plurality of wire filaments joined together at one end and positioned with the other filament ends extending radially outward through one of the passageways in the biasing member, and 
 separate compression springs mounted to extend into each passageway and contact a brush member to bias the brush member radially away from the mandrel. 
 
     
     
       11. The wellbore clean out tool of  claim 10  wherein the passageways in the biasing member is a slot. 
     
     
       12. The wellbore clean out tool of  claim 10  wherein the spring is a coil spring. 
     
     
       13. The wellbore clean out tool of  claim 10  wherein the passageways in the biasing member are bores.